I have an M110 spring (different brand) in my CA M15A4 and it shoots great. The M110 keeps me under 400fps which is good because of my airsoft feilds velcity limit. I have my gun shooting around 370fps. Classic Army, Tokyo Marui, and ICS can all take up to an M120 without any other upgrades. Only use an upgraded spring if you have a metal gearbox. Dont install a spring or any other upgrade parts in your gearbox unless you know how to assemble a gearbox. This spring gets my gun shooting right where I want it.

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About time that shorty got some upgrade parts. This is one sweet spring. The M120 is the best of the three that shorty just barely stocked and this is just like the spring in the ICS MP5 collection that SHORTY USA just stocked! Overall this is one sweet spring and if you can upgrade with Tokyo Mauri parts, BUY
This 15.99 peice of goodness can add up to about 50 dollars in resale value (If yo ever decide to sell this thing). That is a ton of money! Come to think of it, you can MAKE money by buying this. Buy a OK gun, buy this, and tell your friend that your peice of crap M4 auctully gets so much more FPS ($$$$$$$$$$$)
Overall GET THIS

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I know everyone wants the strongest gun possibe, but when upgrading FPS you can decrease RPM and lower the lifespan of the gun. The M110 Spring is great for guns like the CA SAR TAKTIK in which you would not want to sacrfice RPM. The M110 is a perfect balance and I think that this is more practical.

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do not get this if your gun has a plastic piston system or guide bolt. it will most likely end up breaking the gun. i had it in my mp5 and it snaped the bolt clean off when i fired it, and shattered the entire piston assembly. i recently put it in my m4 and it shot about 60 fps faster.

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This spring comes standard with all ECHO 1 AEG's. It produces 340-370 FPS. My ECHO 1 M16A4, ECHO 1 M4, ECHO 1 G36C, and ECHO 1 AK-47 shot at 350 FPS out of the box. My ECHO 1 MP5A4 comes standard with this but it shot at only 330 FPS out of the box. Lube brought up the FPS with all guns.

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This spring was not too bad. It worked and kicked my fps up a bit. But the systema M120 was a bit better. Although the m120 went over our field fps limits, it was much easier to put in the gearbox. This spring was longer and springier too. I would recommend it for those that do have reinforced gearboxes as it will probably crack them or other parts in the gearbox.

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if you just have a few metal internals like your gearbox, piston head, and wiring, then get this, it won't put too much stress on your gun like the M120 will, but it gives good FPS. Still, if you have like a CA ICS (like me) or Mauri, get a m120!

great, buy it, i have it in echo 1,

hope this helped,

thx,

Sunflash out

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Although i do not own this product currently, my friend does and i will tell you this much. I will tsart out with saying that it is high time shorty starts selling upgraded parts. Secondly, this bad boy does what it is meant to do when it comes to upgrading. the quality is ok, and will obviously hold up i mean come on. Anyway it is a good buy for anyone looking to give that gun a little extra pop.

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